Fwd: Re: co adjustments and o2 voltage (was high compression motors in 4kqs)

[Richard J. Andrews]

> > i was trying to get the mixture set on the 4kq  last night and hooked up
> > the multimeter to a ground and used and jumper to connect
> > to the o2 sensor, i was originally getting a littler over 0.9v at wot, and
> > 0.8 at idle after a bit of tweaking it seems to run best with a variance
> > from 0.4 -0.8 i leaned the mixture a bit and at wot now i get 0.84 seems
>to
> > run smoother while cruising it seems to reside between 0.5- 0.7 which i
> > assume is reasonable.
>
> > oh, i was checking DPR current and it seemed pretty fixed at 9.73 is this a
> > bad temp sensor since the o2 sensor is relatively new and seems to be
> > functioning correctly?



>Your post-adjustment o2 numbers seem reasonable to me.
>
>When you were measuring o2, did you unplug the sensor to attach your test
>leads, or leave it connected?  I think if you unplug it, the ECU goes to
>some internal default, resulting in the stable DPR current.  With o2
>connected, my DPR bounces from about 8 to 12mA, averaging the 10mA spec.
my DPR is fluctuating around 15ma, is this too rich or too lean?
i read Huw's website and it says i need to clamp vacuum lines to test this
properly but doesn't specify which ones, it is fluctuating and i have been
checking the 02 voltage with it connected, when decelerating by 02 voltage
goes to 0.0v i think this is normal as this would indicate no fuel.
it seems to run ok like this but would like to figure out why it's not
around 10mv. it goes as high as 18mv at idle. can some cis guru help could
i have a vacuum leak causing the high current or a bad airflow plate assembly?

Thanks!

rich
'86 4kq